Contents
- Weather in May
- Frequently asked questions
- Average temperature in May
- Average pressure in May
- Average wind speed in May
- Average humidity in May
- Average rainfall in May
- Average rainfall days in May
- Average snowfall in May
- Average snowfall days in May
- Average daylight in May
- Average sunshine in May
- Average sunshine days in May
- Average UV index in May
- Average cloud cover in May
- Average visibility in May
Weather in May
Temperature
With the onset of May, the average high-temperature slightly shifts from April's refreshing 58.8°F (14.9°C) to a pleasant 70.7°F (21.5°C). May brings with it a nighttime average temperature of 53.6°F (12°C).Humidity
In May, the average relative humidity is 77%.Rainfall
The month with the most rainfall is May, when the rain falls for 19.4 days and typically aggregates up to 5" (127mm) of precipitation.Snowfall
In Ottawa, Illinois, snow does not fall in May through September.Daylight
In Ottawa, the average length of the day in May is 14h and 31min.On the first day of the month, sunrise is at 5:51 am and sunset at 7:53 pm. On the last day of May, sunrise is at 5:24 am and sunset at 8:21 pm CDT.
Sunshine
In Ottawa, the average sunshine in May is 8.8h.UV index
In Ottawa, Illinois, the average daily maximum UV index in May is 5. A UV Index reading of 3 to 5 represents a medium health hazard from exposure to the Sun's UV radiation for ordinary individuals.Note: A maximum daily UV index of 5 during May morphs into the following directions:
Make use of precautions - Suggestions to resist sunburn are communicated. Given the potency of the midday Sun's UV radiation, one should avoid prolonged exposure. Fend off the sun's harsh rays with appropriate clothing, a wide-brim hat, and UV-protective sunglasses.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What are the temperatures in May?
What is the average humidity in May?
What is the wettest month in Ottawa?
How many days does it rain in May?
When it does not snow?
Does it snow in May?
What is the average length of the day in May?
When are sunrise and sunset in May?
How many hours of sunshine does Ottawa have in May?
What is the UV index intensity in May?
Average temperature in May
Ottawa, IL
- Average high temperature in May: 70.7°F
The warmest month (with the highest average high temperature) is July (81°F).
The month with the lowest average high temperature is January (29.1°F).
- Average low temperature in May: 53.6°F
The month with the highest average low temperature is July (64.2°F).
The coldest month (with the lowest average low temperature) is January (17.2°F).
Average pressure in May
Ottawa, IL
- Average pressure in May: 29.96"Hg
The month with the highest atmospheric pressure is January (30.13"Hg).
The month with the lowest atmospheric pressure is June (29.92"Hg).
Average wind speed in May
Ottawa, IL
- Average wind speed in May: 8.7mph
The windiest month (with the highest average wind speed) is April (10.2mph).
The calmest month (with the lowest average wind speed) is August (6.2mph).
Average humidity in May
Ottawa, IL
- Average humidity in May: 77%
The month with the highest relative humidity is July (85%).
The month with the lowest relative humidity is October (72%).
Average rainfall in May
Ottawa, IL
- Average rainfall in May: 5"
The wettest month (with the highest rainfall) is May (5").
The driest month (with the least rainfall) is November (1.81").
Average rainfall days in May
Ottawa, IL
- Average rainfall days in May: 19.4 days
The month with the highest number of rainy days is July (19.9 days).
The month with the least rainy days is February (6.2 days).
Average snowfall in May
Ottawa, IL
- Average snowfall in May: 0"
The month with the highest snowfall is February (5.08").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days in May
Ottawa, IL
- Average snowfall days in May: 0 days
The month with the highest number of snowfall days is January (12.9 days).
The months with the least snowfall days are May, June, July, August and September (0 days).
Average daylight in May /
Average sunshine in May
Ottawa, IL
- Average daylight in May: 14h and 3min
The month with the longest days is June (Average daylight: 15h and 6min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in May: 8h and 5min
The month with the most sunshine is June (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 3h and 54min).
Average sunshine days in May
Ottawa, IL
- Average sunshine days in May: 9.1 days
The month with the most sunshine days is November (17 days).
The month with the least sunshine days is July (7.2 days).
Average UV index in May
Ottawa, IL
- Average UV index in May: 5
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January and December (UV index 1).
Average cloud cover in May
Ottawa, IL
- Average cloud cover in May: 42
The month with the most cloud cover is January (Cloud cover 59).
The month with the least cloud cover is September (Cloud cover 32).
Average visibility in May
Ottawa, IL
- Average visibility in May: 6mi
The months with the highest visibility are March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are January, February, July and August (5mi).
Ottawa, Illinois, USA
Weather forecast for your location
2. Allow the app to use your location